Product analysis: upon receipt at medtronic's quality laboratory, visual examination revealed evidence of cauterization along the sewing ring.All leaflets were slightly stiff yet flexible.All leaflets were intact except at the dehisced commissures.Thick striations or collagen bands were observed on the outflow of the left cusp.All leaflets were in a closed position, however, due to dehiscence at the left/right and right/non-coronary commissures, all cusps appeared crowded with the non-coronary folded within itself.The left/right and right/non-coronary commissures were dehisced, possibly due to the separation of the layers of the aortic wall behind the commissures.The sutures holding the aortic wall to the stent posts were intact.The left/non-coronary commissure was intact.A thin layer of glistening off-white pannus covered the inflow base stitching extending to the inferior coaptive areas between all leaflets.Remnants of glistening off-white pannus remain attached to the left cusp outflow rail and partially on the non-coronary outflow rail.An unknown amount of pannus may have been removed during explant.Radiography did not reveal calcification on the returned valve.Conclusions: the device history record was reviewed and showed that this product met all manufacturing specifications for product released for distribution.No issues were identified that would have impacted this event.A conclusive cause of the stenosis and regurgitation could not be determined from the limited information available.Based on the risk analysis and historical trend, commissure dehiscence was the most common mechanism which could lead to regurgitation.Without calcification, pannus could have impeded the motion of the leaflets, putting additional stresses on the commissures, ultimately pulling the valve in non-typical directions.Immobile leaflet was one of the most common mechanisms which could lead to stenosis.Pannus would be the common cause for immobile leaflet and is considered to be a patient-related condition.Medtronic is submitting this report to comply with fda reporting regulations under 21 cfr parts 4 and 803.This report is based upon information obtained by medtronic, which the company may not have been able to fully investigate or verify prior to the date the report was required by the fda.Medtronic has made reasonable efforts to obtain more complete information and has provided as much relevant information as is available to the company as of the submission date of this report.This report does not constitute an admission or a conclusion by fda, medtronic, or its employees that the device, medtronic, or its employee caused or contributed to the event described in the report.In particular, this report does not constitute an admission by anyone that the product described in this report has any ¿defects¿ or has ¿malfunctioned¿.These words are included in the fda 3500a form and are fixed items for selection created by the fda to categorize the type of event solely for the purpose of regulatory reporting.Medtronic objects to the use of these words and others like them because of the lack of definition and the connotations implied by these terms.This statement should be included with any information or report disclosed to the public under the freedom of information act.Any required fields that are unpopulated are blank because the information is currently unknown or unavailable.A good faith effort will be made to obtain the applicable information relevant to the report.If information is provided in the future, a supplemental report will be issued.
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